Re: [time-nuts] New ISO8601 ?

So this new revision enables essentially for the encoding of ``ca.''? Obviously the current revision allows for varying degrees of fixed chronological granularity levels. -Ruslan On Thu, Nov 23, 2017 at 9:01 AM, Dana Whitlow wrote: > I believe the phrase "circa 1967" fits

[time-nuts] 53230A weirdness

Hi, all I've done some experiments on my 53230A, and I've come across an issue I think could be worth knowing about. I have not tested this on other 53230A's - if anyone has a 53230A and some spare time, I'd be grateful if someone could try to replicate. In a nutshell, the first frequency

Re: [time-nuts] Symmetricom X72 rubidium oscillator breakout board now avaiable

Well, I ordered one this morning and I am reading the doc I found online. Please save a set of your boards and if you want to send me some heatsinks, I’ll mill them for everyone. Regards, Jerry Jerry Hancock je...@hanler.com (415) 215-3779 > On Nov 20, 2017, at 12:29 AM, Mark Sims

Re: [time-nuts] Next upgrade

The Next upgrade has touched several subjects we deal with on a dayle basis. Allow mw to add my thoughts. First we are time nuts trying within our limits to advance time and frequency generation and measurement with affordable resources. We are at least a factor four orders of magnitude

Re: [time-nuts] New ISO8601 ?

I believe the phrase "circa 1967" fits the bill pretty well, although it may fall a little bit short of "...but it’s all a bit of a blur”. Dana On Thu, Nov 23, 2017 at 7:18 AM, Poul-Henning Kamp wrote: > > In message <4bec82c4-583e-4632-8589-d898cc2bd...@n1k.org>,

Re: [time-nuts] Allan variance by sine-wave fitting

The harmonics limit the perfomance if you want to find the frequency of a given, sampled sinewave with linear methods. Thats at least my finding when I built a device to measure grid frequency fast and with high accuracy. I had to use high-Q digital filters for the fundamental. Their slow

Re: [time-nuts] Allan variance by sine-wave fitting

I wonder how much a fitting approach is affected by distortion (especially harmonic content) in the waveform. Of course we can always filter the waveform to make it more sinusoidal but then we are adding L's and C's and their tempcos to the measurement for sure destroying any femtosecond claims.

Re: [time-nuts] Allan variance by sine-wave fitting

Hi, There is trivial ways to estimate phase and amplitude of a sine using linear methods. I saw however none of these properly referenced or described. It would have been good to see those approaches attempted in parallel on the same data and compare their performance with the proposed

Re: [time-nuts] New ISO8601 ?

HI > On Nov 23, 2017, at 8:18 AM, Poul-Henning Kamp wrote: > > > In message <4bec82c4-583e-4632-8589-d898cc2bd...@n1k.org>, Bob kb8tq writes: > >> I had never realized there was a format for expressing “I think it was 1967 >> but it’s >> all a bit of a blur”. >

Re: [time-nuts] New ISO8601 ?

In message <4bec82c4-583e-4632-8589-d898cc2bd...@n1k.org>, Bob kb8tq writes: >I had never realized there was a format for expressing “I think it was 1967 >but it’s >all a bit of a blur”. I think that is one of the major reasons for the revision. -- Poul-Henning Kamp | UNIX

Re: [time-nuts] Allan variance by sine-wave fitting

Hi One other side to this: There are a number of papers out there on this basic technique (ADC frequency measurement). There are a number of commercial products that do ADEV and other measurements this way. It might be a good idea to at least mention them. It would be even better to look at

Re: [time-nuts] Next upgrade

Hi Yes, the “has no GPS” box becomes the active device in a REF0 / REF1 pair. If a survey is involved, it can take a *long* time for things to sort out. Bob > On Nov 23, 2017, at 7:22 AM, Adrian Godwin wrote: > > Turns out is does work - Initially, when I linked them,

Re: [time-nuts] New ISO8601 ?

Hi I had never realized there was a format for expressing “I think it was 1967 but it’s all a bit of a blur”. Bob > On Nov 23, 2017, at 4:57 AM, Poul-Henning Kamp wrote: > > Seems there is an ISO8601 revision in progress ? > > https://www.loc.gov/standards/datetime/ >

Re: [time-nuts] Allan variance by sine-wave fitting

Hi, just my two cents on sine wave fitting. A undamped sine wave is the solution of the difference equation sig(n+1)=2*cos(w)*sig(n)-sig(n-1) This is a linear system of equations mapping the sum of the samples n+1 and n-1 to the sample n. The factor 2*cos(w) is the unknown. The least-squares

Re: [time-nuts] Next upgrade

Turns out is does work - Initially, when I linked them, both boxes had the standby light go out and the unmodified ref-0 (with no GPS receiver) showed Fault and No GPS. So I assumed there was some problem that might be causing them to conflict over the interface, and unplugged it. I've tried it

[time-nuts] New ISO8601 ?

Seems there is an ISO8601 revision in progress ? https://www.loc.gov/standards/datetime/ -- Poul-Henning Kamp | UNIX since Zilog Zeus 3.20 p...@freebsd.org | TCP/IP since RFC 956 FreeBSD committer | BSD since 4.3-tahoe Never attribute to malice what can adequately be

Re: [time-nuts] Next upgrade

I once did make a token attempt at tweaking the disciplining parameters in that SRS-10, but seemed to be getting nowhere and gave up on the effort. Dana On Wed, Nov 22, 2017 at 8:12 PM, Mark Sims wrote: > The PRS-10 does have disciplining parameters that you can tweak.